polyd3
http://www.openmath.org/cd/polyd3.ocd
2006-04-01
2004-07-07
experimental
1
0
This CD contains conversions between different data structures for polynomials.
first attempt
collect
This a binary function. Its first argument should be a DMP f, its second
argument a list of positive integers L.
When applied to f and L, it represents the DMP with coefficients from the poly_ring_d
whose variables only have indices i for i not occurring in the list L, and
whose monomials are built up from the variables indexed by the entries
of L.
list_to_poly_d
This symbol is a function with two arguments.
The first argument is a ring R and the second argument is a list L. The
entries of L are elements of R or can be cast canconically onto
elements of R.
When applied to R and L, the symbol denotes the distributed (univariate)
polynomial over R with terms (L[i-1],i) for i running over the indices
of L (i=1, ..., length(L)).
The polynomial X^2+4X+7 with integers coefficients can be represented,
without recourse to X, by
741
Thus, the above expression is semantically equivalent to
70
41
12
poly_d_to_arith
This symbol is a binary function.
The first argument is a DMP and the second argument is a list of objects,
typically variables or arithmetic expressions, at least as
many as there are variables in the ring to which the DMP belongs.
When applied to R and L, the symbol denotes the arithmetic expression that is
the sum of the terms
with the i-th variable of the ring of the DMP being substituted by the i-th expression or variable of
the list L.
This expression is very close to a substitute, or an application of the DMP, as
viewed as a function, to
as many arguments as there are variables.
The polynomial X^2+4X+7 with integer coefficients
has poly_d form
1
70
41
12
This expression represents
7
4
2
poly_d_named_to_arith
This symbol is a unary function.
Its argument is a DMP with named variables.
When applied to R, the symbol denotes the arithmetic expression that is
the sum of the terms.
The polynomial X^2+4X+7 with integers coefficients
has poly_d_named form
70
41
12
This expression represents
7
4
2